Assessing decision-making capacity in dementia patients: a semi-structured approach.

One of the consequences of the rapidly increasing numbers of dementia patients in Singapore will be the need for all clinicians (including non-psychiatrists) to be familiar with the fundamentals of how decision-making capacity should be assessed. The clinical settings when the need for such evaluations arise, often involve cognitively or emotionally impaired patients who are required to make treatment, placement, financial or testamentary decisions. The clinician must first diagnose the patient's psychopathology and then go onto testing the functional abilities involved in decision-making. These comprise (1) making and expressing a choice, (2) understanding the relevant information, (3) appreciating the relevance of the information to oneself and (4) reasoning with the given information. The eventual judgement of the patient's decision-making capacity involves the weighing of impairment noted in any of the four decisional abilities against the potential adverse consequences of abiding by the patient's decision. The ethical impulse underlying this manner of judgement balances the respecting of patient's autonomy with protecting the patient from harm. Given the relative complexity of the assessment process, there is merit in developing a semi-structured approach to the evaluation of patients' decision-making capabilities; such an approach can guide a wider group of clinicians and psychologists through the essential steps of the process and thus enable the assessment to be more thorough, as well as fairer, to the patient.